CLEANING PROCESS

Abstract

Process for cleaning dishes in a dishwasher during which the aqueous washing liquor contained in the interior of the dishwasher is at least partly removed from the interior of the dishwasher at a point in time t. The process involves metering a dishwasher detergent A containing one or more surfactants and one or more anionic polymers at a time t1<t in an amount m1 and at a time t2>t in an amount m2 into the interior of the dishwasher. The process according to the invention differs from conventional cleaning processes in that formation of deposits is reduced and drying efficiency improved.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of International Patent Application No. PCT/EP2008/056343 filed 23 May 2008, which claims priority to German Patent Application No. 10 2007 042 859.8 filed 10 Sep. 2007, both of which are incorporated herein by reference.

The present application relates to a process for cleaning tableware. In particular, this application relates to a process for cleaning tableware wherein cleaning agents are metered into the interior of an automatic dishwasher in a time delay fashion.

Dishwashing agents are available to the consumer in numerous presentation forms. In addition to traditional liquid hand dishwashing detergents, automatic dishwashing agents have become highly important due to the growing use of automatic dishwashers. These automatic dishwashing agents are typically offered to the consumer in solid form, for example, as a powder or as tablets, but increasingly also in liquid form.

One of the main aims of automatic cleaning agent manufacturers is to improve the cleaning performance of these agents, with greater emphasis focused on cleaning performance in low temperature cleaning cycles or in cleaning cycles with reduced water consumption. With this in mind, preferably novel ingredients, for example, more active surfactants, polymers or bleaching agents, have been added to the cleaning agents. As these novel ingredients are available only to a limited extent, and as the added amount of ingredient per cleaning cycle can not be increased above a certain amount due to environmental and economic grounds, this approach has only limited possibilities.

Another approach for improving the performance profile of existing washing or cleaning agents involves the development of novel manufactured forms, for example, by combining solid and liquid washing or cleaning agent ingredients. Suitable cleaning agents are combined with one another, for example, in new types of water-soluble packaging.

The present application provides an improvement in the known processes for automatic dishwashing in such a way that these processes exhibit an improved cleaning performance as well as an improved drying of the cleaned tableware, without the addition of further ingredients or increase in the metered quantities, even for low temperature cleaning cycles or for cleaning cycles with reduced water consumption.

This improvement was achieved by a specific dishwashing process wherein a surfactant- and polymer-containing cleaning agent is metered into the interior of an automatic dishwasher on a time delay.

Accordingly, in one embodiment the present application is a process for cleaning tableware in an automatic dishwasher. According to the process, aqueous wash liquor present in the interior of the automatic dishwasher is at least partially removed from the interior of the automatic dishwasher at a time t. Further,

a) one or more surfactants, and

b) one or more anionic polymers

are metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

The inventive process can be carried out in the interior of a commercial automatic dishwasher, particularly, a commercial domestic automatic dishwasher.

The automatic cleaning program for an automatic dishwasher is generally chosen by the user before the dishwashing process is carried out from a list of set programs, wherein for this, particularly temperature of the wash liquor during the cleaning process, duration of the process or the added cleaning agent and cleaning agent auxiliaries, are defined (e.g., “2 in 1” and “3 in 1” programs).

Independent of temperature and cycle length, the automatic dishwasher process or user-selected cleaning program of the dishwasher can have at least two washing cycles, such as a pre-wash cycle, a cleaning cycle and a rinse cycle. These washing cycles vary, for example, by duration, water consumption and/or temperature sequence, during which the aqueous cleaning liquor present in the interior of the automatic dishwasher is at least partially removed from the interior of the automatic dishwasher between washing cycles, and optionally replenished with added fresh water. This exchange of washing liquor is generally accomplished by a pump system integrated in the dishwasher.

The partial pumping out of the wash liquor from the interior of the automatic dishwasher preferably occurs so that at least about 5 vol. %, preferably about 10 vol. %, particularly preferably at least about 20 vol. %, quite particularly preferably at least about 40 vol. % and especially at least about 60 vol. % of the wash liquor is pumped out of the interior of the dishwasher. In particularly preferred processes, from about 5 to about 99 vol. % of the wash liquor, preferably from about 10 to about 90 vol. % of the wash liquor and particularly preferably from about 20 to about 80 vol. % and especially from about 40 to about 70 vol. % of the wash liquor is pumped out.

Accordingly, another embodiment of the present application is a process for cleaning tableware in an automatic dishwasher. During the process aqueous wash liquor present in the interior of the automatic dishwasher is removed from the interior of the dishwasher at a time t in an amount of from about 5 to about 99 vol. %, preferably from about 10 to about 90 vol. %, and particularly preferably from about 20 to about 80 vol. % and especially from about 40 to about 70 vol. % of the wash liquor. According to the process, an automatic dishwashing agent A comprising—

a) one or more nonionic surfactants and

b) one or more anionic polymers

is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

The wash liquor can be completely pumped out; however, complete removal of the wash liquor from the interior of the dishwasher requires a comparatively long time and energy expenditure, and is therefore less preferred.

According to the inventive process, both before and after the wash liquor has been at least partially pumped out of the interior of the dishwasher an automatic dishwashing agent comprising nonionic surfactants and anionic polymers is metered into the interior of the dishwasher, and thus into the wash liquor located in the interior. The length of time between metering times t1 and t2 can vary, wherein the time difference between the times t1 and t2 can be about 5 to about 50 minutes, preferably about 10 to about 40 minutes and especially about 15 to about 30 minutes.

Temperature of the wash liquor at time t1 is preferably from about 12 to about 45° C., particularly from about 15 to about 40° C., and especially from about 20 to about 35° C., and at time t2 is preferably from about 30 to about 65° C., particularly from about 35 to about 60° C., and especially from about 40 to about 55° C. In a particularly preferred embodiment of the inventive process, the temperature of the wash liquor at time t2 is above the temperature of the wash liquor at time t1. A suitable temperature sequence wherein the temperature of the wash liquor at time t2 is above the temperature of the wash liquor at time t1, has proven to be superior in regard to the cleaning and rinsing performance.

Alternatively, the inventive dishwashing process can also be carried out so that the temperature of the wash liquor at time t2 is below or identical to the temperature of the wash liquor at time t1.

In preferred process variants, the weight ratio of the metered amounts m1 and m2 is from about 20:1 to about 2:1, particularly from about 15:1 to about 3:1 and especially from about 12:1 to about 4:1.

A characteristic of the automatic dishwashing agents employed in the inventive process is their content of surfactants and anionic polymers.

Nonionic surfactants, anionic surfactants, and amphoteric surfactants have proven to be particularly effective with respect to cleaning power and drying, wherein from this group of surfactants, nonionics provided best results, with anionic and amphoteric surfactants being preferably employed in combination with defoamers or foam inhibitors.

All nonionic surfactants known to the person skilled in the art can be used as the nonionic surfactant(s). Suitable exemplary nonionic surfactants include alkyl glycosides that satisfy the general Formula RO(G)_x, wherein R is a primary linear or methyl-branched, particularly 2-methyl-branched, aliphatic group containing 8 to 22 and preferably 12 to 18 carbon atoms; and G is a glycose unit containing 5 or 6 carbon atoms, preferably glucose. The degree of oligomerization x, which defines the distribution of monoglycosides and oligoglycosides, is any number from 1.0 to 10, preferably 1.2 to 1.4.

Nonionic surfactants of the amine oxide type such as N-cocoalkyl-N,N-dimethylamine oxide and N-tallow alkyl-N,N-dihydroxyethylamine oxide, as well as fatty acid alkanolamides may also be suitable. The quantity in which these nonionic surfactants are used is preferably no more than the quantity in which the ethoxylated fatty alcohols are used, and particularly no more than half that quantity.

Another class of preferred nonionic surfactants which may be used, either as the sole nonionic surfactant or in combination with other nonionic surfactants, is alkoxylated, preferably ethoxylated or ethoxylated and propoxylated fatty acid alkyl esters preferably containing 1 to 4 carbon atoms in the alkyl chain.

Preferred surfactants include weakly foaming nonionic surfactants. Washing or cleaning compositions, particularly cleaning compositions for automatic dishwashers, are especially preferred when they comprise nonionic surfactants from the alkoxylated alcohols. Preferred nonionic surfactants include alkoxylated, advantageously ethoxylated, particularly primary alcohols preferably containing 8 to 18 carbon atoms and, on average, 1 to 12 moles of ethylene oxide (EO) per mole of alcohol, wherein the alcohol group can be linear or, preferably, methyl-branched in the 2-position or can contain, for example, linear and methyl-branched groups in the form of mixtures typically present in oxo alcohol groups. Particularly preferred are, however, alcohol ethoxylates with linear groups from alcohols of natural origin with 12 to 18 carbon atoms (e.g., from coco-, palm-, tallow- or oleyl alcohol) and an average of 2 to 8 EO per mol alcohol. Exemplary preferred ethoxylated alcohols include C_12-13 alcohols with 3 EO or 4 EO, C_9-11 alcohols with 7 EO, C_13-15 alcohols with 3 EO, 5 EO or 7 EO, C_12-18 alcohols with 3 EO, 5 EO or 7 EO and mixtures thereof, such as mixtures of C_12-14 alcohol with 3 EO and C_12-18 alcohol with 5 EO. The cited degrees of ethoxylation constitute statistically average values that can be a whole or a fractional number for a specific product. Preferred alcohol ethoxylates have a narrowed homolog distribution (narrow range ethoxylates, NRE). In addition to these nonionic surfactants, fatty alcohols with more than 12 EO can also be used. Examples of these are tallow fatty alcohol with 14 EO, 25 EO, 30 EO or 40 EO.

Accordingly, ethoxylated nonionic surfactant(s) prepared from C_6-20 monohydroxy alkanols or C_6-20 alkyl phenols or C_12-20 fatty alcohols and more than 12 mole, preferably more than 12 mole and especially more than 20 mole ethylene oxide per mole alcohol, are used with particular preference. A particularly preferred nonionic surfactant is obtained from a straight-chain fatty alcohol containing 16 to 20 carbon atoms (C_16-20 alcohol), preferably a C_1-8 alcohol, and at least 12 moles, preferably at least 15 moles and more preferably at least 20 moles of ethylene oxide. Of these nonionic surfactants, the so-called narrow range ethoxylates are particularly preferred. Moreover, combinations of one or more tallow fat alcohols with 20 to 30 EO with a silicone defoamer are particularly preferably used.

Nonionic surfactants having a melting point above room temperature are used with particular preference. Nonionic surfactant(s) with a melting point above about 20° C., preferably above about 25° C., particularly preferably from about 25 to about 60° C. and especially from about 26.6 to about 43.3° C., is/are particularly preferred.

Suitable nonionic surfactants with a melting and/or softening point in the cited temperature range include, for example, weakly foaming nonionic surfactants that can be solid or highly viscous at room temperature. If nonionic surfactants are used that are highly viscous at room temperature, then it is preferred that they have a viscosity greater than about 20 Pa s, preferably above about 35 Pa s, and especially above about 40 Pa s. Nonionic surfactants having a waxy consistency at room temperature are also preferred, depending on application.

Nonionic surfactants from the alkoxylated alcohols, particularly preferably from the mixed alkoxylated alcohols, and especially from the EO-AO-EO-nonionic surfactants are likewise incorporated with particular preference.

Preferably, the nonionic surfactant solid at room temperature additionally has propylene oxide units in the molecule. These PO units preferably make up as much as about 25% by weight, more preferably as much as about 20% by weight and, especially up to about 15% by weight of the total molecular weight of the nonionic surfactant. Particularly preferred nonionic surfactants include ethoxylated monohydroxyalkanols or alkylphenols, which have additional polyoxyethylene-polyoxypropylene block copolymer units. The alcohol or alkylphenol component of these nonionic surfactant molecules preferably makes up about 30 wt. % or more, more preferably about 50 wt. % or more, and most preferably about 70 wt. % or more of the total molecular weight of these nonionic surfactants. Preferred compositions comprise ethoxylated and propoxylated nonionic surfactants in which the propylene oxide units in the molecule preferably make up as much as about 25% by weight, more preferably as much as about 20% by weight and, especially up to about 15% by weight of the total molecular weight of the nonionic surfactant.

Preferred surfactants that are solid at room temperature are used and belong to the groups of the alkoxylated nonionic surfactants, more particularly the ethoxylated primary alcohols, and mixtures of these surfactants with structurally more complex surfactants, such as polyoxypropylene/polyoxyethylene/polyoxypropylene ((PO/EO/PO) surfactants). Such (PO/EO/PO)-nonionic surfactants are moreover characterized as having good foam control.

Other particularly preferred nonionic surfactants with melting points above room temperature comprise about 40 to about 70% of a polyoxypropylene/polyoxyethylene/polyoxypropylene block polymer blend having about 75% by weight of an inverted block copolymer of polyoxyethylene and polyoxypropylene with 17 moles of ethylene oxide and 44 moles of propylene oxide and about 25% by weight of a block copolymer of polyoxyethylene and polyoxypropylene initiated with trimethylol propane and comprising 24 moles of ethylene oxide and 99 moles of propylene oxide per mole of trimethylol propane.

Particularly preferred nonionic surfactants in the context of the present invention include weakly foaming nonionic surfactants having alternating ethylene oxide and alkylene oxide units. Among these, surfactants with EO-AO-EO-AO blocks are again preferred, wherein one to ten EO or AO groups respectively are linked together before a block of the other groups follows. Here, nonionic surfactants of the general formula—

are preferred, wherein R¹ is a linear or branched, saturated or a mono- or polyunsaturated C_6-24-alkyl or alkenyl group; R² and R³ are independently —CH₃, —CH₂CH₃, —CH₂CH₂—CH₃, CH(CH₃)₂; and the indices w, x, y, z are independently whole numbers from 1 to 6.

The preferred nonionic surfactants of the previous formula can be manufactured by known methods from the corresponding alcohols R¹—OH and ethylene- or alkylene oxide. R¹ in the previous Formula can vary depending on the origin of the alcohol. When natural sources are used, R¹ has an even number of carbon atoms and generally is not branched. Linear alcohols of natural origin with 12 to 18 carbon atoms (e.g., coconut, palm, tallow or oleyl alcohol) are preferred. Alcohols available from synthetic sources include, for example, Guerbet alcohols or mixtures of methyl branched in the 2-position or linear and methyl branched groups, as are typically present in oxo alcohols. Independent of the type of alcohol used for the manufacture of nonionic surfactants present in the compositions, nonionic surfactants are preferred, wherein R¹ in the previous formula stands for an alkyl group containing 6 to 24, preferably 8 to 20, particularly preferably 9 to 15 and particularly 9 to 11 carbon atoms.

In addition to propylene oxide, butylene oxide can especially be the alkylene oxide unit that alternates with the ethylene oxide unit in the preferred nonionic surfactants. However, other alkylene oxides are also suitable, wherein R² or R³ independently are —CH₂CH₂—CH₃ or CH(CH₃)₂. Preferably, nonionic surfactants of the previous formula are used wherein R² or R³ is —CH₃, w and x independently are values of 3 or 4, and y and z independently are values of 1 or 2.

In summary, nonionic surfactants that are especially preferred have a C_9-15-alkyl group with 1 to 4 ethylene oxide units, followed by 1 to 4 propylene oxide units, followed by 1 to 4 ethylene oxide units, followed by 1 to 4 propylene oxide units. These surfactants exhibit the required low viscosity in aqueous solution and according to the invention are used with particular preference.

Surfactants of the general formula R¹—CH(OH)CH₂O-(AO)_w-(A′O)_x-(A″O)_y-(A″O)_z—R², wherein R¹ and R² independently are a linear or branched, saturated or unsaturated or mono- or polyunsaturated C_2-40 alkyl or alkenyl group; A, A′, A″ and A′″ independently are —CH₂CH₂, —CH₂CH₂—CH₂, —CH₂—CH(CH₃), —CH₂—CH₂—CH₂—, —CH₂—CH(CH₃)—CH₂—, or —CH₂—CH(—CH₂—CH₃); and w, x, y and z are values from 0.5 to 90, wherein x, y and/or z can also be 0, are preferred.

End-capped polyoxyalkylated nonionic surfactants are particularly preferred that, according to the formula R¹O[CH₂CH₂O]_xCH2CH(OH)R², possess, in addition to an R¹ that is a linear or branched, saturated or unsaturated, aliphatic or aromatic hydrocarbon groups containing 2 to 30 carbon atoms, preferably containing 4 to 22 carbon atoms, contains a further linear or branched, saturated or unsaturated, aliphatic or aromatic hydrocarbon group R² containing 1 to 30 carbon atoms, wherein x is a value from 1 to 90, preferably a value from 30 to 80, and especially a value from 30 to 60.

Particularly preferred surfactants are those according to the formula R¹O[CH₂CH(CH₃)O]_x[CH₂CH₂O]_yCH₂CH(OH)R², wherein R¹ is a linear or branched aliphatic hydrocarbon group containing 4 to 18 carbon atoms or mixtures thereof; R² is a linear or branched hydrocarbon group containing 2 to 26 carbon atoms or mixtures thereof; x is a value from 0.5 to 1.5; and y is a value of at least 15.

Further particularly preferred are those end-capped poly(oxyalkylated) nonionic surfactants of the formula R¹O[CH₂CH₂O]_x[CH₂CH(R³)O]_yCH₂CH(OH)R², wherein R¹ and R² independently are linear or branched, saturated or mono- or polyunsaturated hydrocarbon groups containing 2 to 26 carbon atoms; R³ is —CH₃, —CH₂CH₃, —CH₂CH₂—CH₃, or —CH(CH₃)₂, preferably —CH₃; and x and y independently of are a value from 1 to 32, wherein surfactants with R³=—CH₃, x is a value from 15 to 32, and y is a value from 0.5 to 1.5 are quite particularly preferred.

By adding the above-described nonionic surfactants containing a free hydroxyl group on one or both terminal alkyl groups, formation of deposits in the automatic dishwashing can be significantly reduced compared to conventional polyalkoxylated fatty alcohols without free hydroxyl groups.

Further preferred suitable nonionic surfactants include end-blocked poly(oxyalkylated) nonionic surfactants of the formula R¹O[CH₂CH(R³)O]_x[CH₂]_kCH(OH)[CH₂]_jOR², in which R¹ and R² stand for linear or branched, saturated or unsaturated, aliphatic or aromatic hydrocarbon groups containing 1 to 30 carbon atoms, R³ stands for H or for a methyl, ethyl, n-propyl, isopropyl, n-butyl, 2-butyl or 2-methyl-2-butyl group, x for values between 1 and 30, k and j have values between 1 and 12, preferably between 1 and 5. Each R³ in the above formula R¹O[CH₂CH(R³)O]_x[CH₂]_kCH(OH)[CH₂]_jOR² can be different for the case where x≧2. R¹ and R² are preferably linear or branched, saturated or unsaturated, aliphatic or aromatic hydrocarbon groups containing 6 to 22 carbon atoms, groups containing 8 to 18 carbon atoms being particularly preferred. H, —CH₃ or —CH₂CH₃ are particularly preferred for the group R³. Particularly preferred values for x are in the range from 1 to 20 and more particularly in the range from 6 to 15.

As described above, each R³ in the above formula can be different for the case where x≧2. In this manner the alkylene oxide unit in the straight brackets can be varied. If, for example, x has a value of 3, then the substituent R³ can be selected to form ethylene oxide (R³═H) or propylene oxide (R³═CH₃) units which can be joined together in any order, for example, (EO)(PO)(EO), (EO)(EO)(PO), (EO)(EO)(EO), (PO)(EO)(PO), (PO)(PO)(EO) and (PO)(PO)(PO). The value 3 for x was selected by way of example and may easily be larger, the range of variation increasing with increasing x-values and including, for example, a large number of (EO) groups combined with a small number of (PO) groups or vice versa.

Particularly preferred end-capped poly(oxyalkylated) alcohols corresponding to the above formula have values for both k and j of 1, so that the above formula can be simplified to R¹O[CH₂CH(R³)O]_xCH₂CH(OH)CH₂OR². In this last formula, R¹, R² and R³ are as defined above and x stands for numbers from 1 to 30, preferably 1 to 20 and especially 6 to 18. Surfactants in which the substituents R1 and R2 have 9 to 14 carbon atoms, R³ stands for H and x assumes values of 6 to 15 are particularly preferred.

The cited carbon chain lengths and degrees of ethoxylation or alkoxylation of the abovementioned nonionic surfactants constitute statistically average values that can be a whole or a fractional number for a specific product. Due to the manufacturing processes, commercial products of the cited formulas do not consist in the main of one sole representative, but rather are a mixture, wherein not only the carbon chain lengths but also the degrees of ethoxylation or alkoxylation can be average values and thus be fractional numbers.

Of course, the abovementioned nonionic surfactants can not only be employed as single substances, but also as surfactant mixtures of two, three, four or more surfactants. Accordingly, surfactant mixtures do not refer to mixtures of nonionic surfactants that as a whole fall under one of the above cited general formulas, but rather refer to such mixtures that comprise two, three, four or more nonionic surfactants that can be described by the different abovementioned general formulas.

In preferred process variants the automatic dishwashing agent A comprises nonionic surfactant(s) in quantities of about 0.1 to about 30 wt. %, preferably about 0.2 to about 20 wt. %, particularly preferably about 0.5 to about 10 wt. % and especially from about 1 to about 8 wt. %, each based on the total weight of the automatic dishwashing agent A. Particularly preferred process variants are those in which the automatic dishwashing agent A comprises the nonionic surfactant in amounts of about 0.5 to about 5.0 wt. %, based on the total weight of the automatic dishwashing agent A.

Accordingly, a preferred subject matter of the present application is a process for cleaning tableware in an automatic dishwasher, during which the aqueous cleaning liquor that is present in the interior of the automatic dishwasher is at least partially removed from the interior of the automatic dishwasher at a time t, wherein an automatic dishwashing agent A, comprising, based on total weight of the automatic dishwashing agent A—

a) 0.5 to 5 wt. % nonionic surfactant(s), and

b) anionic polymer(s)

is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

Accordingly, a further preferred subject matter of the present application is a process for cleaning tableware in an automatic dishwasher, during which aqueous wash liquor present in the interior of the automatic dishwasher is removed therefrom in an amount of about 5 to about 99 vol. %, preferably from about 10 to about 90 vol. %, particularly preferably from about 20 to about 80 vol. % and especially from about 40 to about 70 vol. % at a time t. Further, an automatic dishwashing agent A comprising, based on total weight of the automatic dishwashing agent A—

a) 0.5 to 10 wt. % nonionic surfactant(s), and

b) anionic polymer(s)

is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

Alternatively or in addition to the nonionic surfactants, anionic or amphoteric surfactants, preferably in combination with defoamers or foam inhibitors, can also be employed in the inventive automatic dishwashing process.

Exemplary suitable anionic surfactants include those of the sulfonate and sulfate type. Suitable surfactants of the sulfonate type include, advantageously C_9-13 alkylbenzene sulfonates, olefin sulfonates (i.e., mixtures of alkene- and hydroxyalkane sulfonates) and disulfonates, as are obtained, for example, from C_12-18 monoolefins having a terminal or internal double bond, by sulfonation with gaseous sulfur trioxide and subsequent alkaline or acidic hydrolysis of the sulfonation products. Alkane sulfonates, obtained for example from C_12-18 alkanes by sulfochlorination or sulfoxidation with subsequent hydrolysis or neutralization, are also suitable. Esters of α-sulfofatty acids (ester sulfonates) (e.g., α-sulfonated methyl esters of hydrogenated coco-, palm nut- or tallow fatty acids) are likewise suitable.

Further suitable anionic surfactants include sulfated fatty acid esters of glycerin. They include the mono-, di- and triesters and also mixtures of them, such as those obtained by esterification of a monoglycerin with 1 to 3 moles fatty acid, or by transesterification of triglycerides with 0.3 to 2 moles glycerin. Preferred sulfated fatty acid esters of glycerin in this case are the sulfated products of saturated fatty acids containing 6 to 22 carbon atoms (e.g., caproic acid, caprylic acid, capric acid, myristic acid, lauric acid, palmitic acid, stearic acid or behenic acid).

Preferred alk(en)yl sulfates include the alkali metal and especially sodium salts of the sulfuric acid half-esters derived from C₁₂-C₁₈ fatty alcohols (e.g., from coconut butter alcohol, tallow alcohol, lauryl, myristyl, cetyl or stearyl alcohol) or from C₁₀-C₂₀ oxo alcohols and those half-esters of secondary alcohols of these chain lengths. Additionally preferred are alk(en)yl sulfates of the said chain lengths containing a synthetic, straight-chained alkyl group produced on a petrochemical basis and showing similar degradation behavior to suitable compounds based on fat chemical raw materials. C₁₂-C₁₆ alkyl sulfates and C₁₂-C₁₅ alkyl sulfates and C₁₄-C₁₅ alkyl sulfates are preferred because of their washing performance. 2,3-Alkyl sulfates, which can be obtained from the Shell Oil Company under the trade name DAN®, are also suitable anionic surfactants.

Sulfuric acid mono-esters derived from straight-chained or branched C_7-21 alcohols ethoxylated with 1 to 6 moles ethylene oxide are also suitable, for example, 2-methyl-branched C_9-11 alcohols with an average of 3.5 mole ethylene oxide (EO) or C_12-18 fatty alcohols with 1 to 4 EO. Due to their high foaming performance, they are only used in fairly small quantities in cleaning compositions, for example, in amounts of 1 to 5% by weight.

Other suitable anionic surfactants include the salts of alkylsulfosuccinic acid, also referred to as sulfosuccinates or esters of sulfosuccinic acid and the monoesters and/or di-esters of sulfosuccinic acid with alcohols, preferably fatty alcohols and especially ethoxylated fatty alcohols. Preferred sulfosuccinates comprise C_8-18 fatty alcohol groups or mixtures of them. Especially preferred sulfosuccinates contain a fatty alcohol group derived from the ethoxylated fatty alcohols that are under consideration as nonionic surfactants. Once again the particularly preferred sulfosuccinates are those, whose fatty alcohol groups are derived from ethoxylated fatty alcohols with narrow range homolog distribution. It is also possible to use alk(en)ylsuccinic acids with preferably 8 to 18 carbon atoms in the alk(en)yl chain, or salts thereof.

Suitable exemplary amphoteric surfactants include betaines or alkylamido alkylamines.

Suitable betaines include alkyl betaines, alkylamido betaines, imidazolium betaines, sulfo betaines (INCI sultaines), as well as phospho betaines, preferably satisfying the formula (R^A)(R^B)(R^C))N⁺CH₂COO⁻, wherein R^A is an alkyl group with 8 to 25, preferably 10 to 21 carbon atoms, optionally interrupted by heteroatoms or heteroatomic groups, and R^B and R^C are the same or different alkyl groups with 1 to 3 carbon atoms, in particular C₁₀-C₂₂ alkyldimethylcarboxymethylbetaine and C₁₁-C₁₇ alkylamido propyldimethylcarboxymethylbetaine, or formula

R¹—[CO—X—(CH₂)_n]_x—N⁺(R^II)(R^III)—(CH₂)_m-[CH(OH)—CH₂]_y—Y⁻

wherein R¹ is a saturated or unsaturated C_6-22 alkyl group, preferably C_8-18 alkyl group, more preferably a saturated C_10-16 alkyl group, for example, a saturated C_12-14 alkyl group; X is NH, NR^IV with the C_1-4 alkyl group R^IV, O or S; n is a number from 1 to 10, preferably 2 to 5, particularly 3; x is 0 or 1, preferably 1; R^II and R^III are independently a C_1-4 alkyl group, an optionally hydroxy substituted group, such as a hydroxyethyl group, but especially a methyl group; m is a number from 1 to 4, particularly 1, 2 or 3; y is 0 or 1; and Y is COO, SO₃, OPO(OR^V)O or P(O)(OR^V)O, wherein R^V is a hydrogen atom H or a C_1-4 alkyl group.

Alkyl betaines and alkylamido betaines corresponding to the above formula with a carboxylate group (Y⁻═COO⁻) are also known as carbobetaines.

Preferred amphoteric surfactants include alkyl betaines corresponding to formula (A1), allylamido betaines corresponding to formula (A2), sulfo betaines corresponding to formula (A3) and amido sulfo betaines corresponding to formula (A4) below:

R¹—N⁺(CH₃)₂—CH₂COO⁻  (A1)

R¹—CO—NH—(CH₂)₃—N⁺(CH₃)₂—CH₂COO⁻  (A2)

R¹—N⁺(CH₃)₂—CH₂CH(OH)CH₂SO₃⁻  (A3)

R¹—CO—NH—(CH₂)₃—N⁺(CH₃)₂—CH₂CH(OH)CH₂SO₃⁻  (A4)

wherein R¹ has the same meaning as in Formula A.

Particularly preferred amphoteric surfactants are the carbobetaines, and more particularly carbobetaines corresponding to formulae (A1) and (A2), alkylamido betaines corresponding to formula (A2) being most particularly preferred. Exemplary suitable betaines and sulfo betaines include the following compounds named according to INCI: Almondamidopropyl Betaine, Apricotamidopropyl Betaine, Avocadamidopropyl Betaine, Babassuamidopropyl Betaine, Behenamidopropyl Betaine, Behenyl Betaine, Betaine, Canolamidopropyl Betaine, Capryl/Capramidopropyl Betaine, Carnitine, Cetyl Betaine, Cocamidoethyl Betaine, Cocamidopropyl Betaine, Cocamidopropyl Hydroxysultaine, Coco-Betaine, Coco-Hydroxysultaine, Coco/Oleamidopropyl Betaine, Coco-Sultaine, Decyl Betaine, Dihydroxyethyl Oleyl Glycinate, Dihydroxyethyl Soy Glycinate, Dihydroxyethyl Stearyl Glycinate, Dihydroxyethyl Tallow Glycinate, Dimethicone Propyl PG-Betaine, Erucamidopropyl Hydroxysultaine, Hydrogenated Tallow Betaine, Isostearamidopropyl Betaine, Lauramido propyl Betaine, Lauryl Betaine, Lauryl Hydroxysultaine, Lauryl Sultaine, Milkamidopropyl Betaine, Minkamidopropyl Betaine, Myristamidopropyl Betaine, Myristyl Betaine, Oleamidopropyl Betaine, Oleamidopropyl Hydroxysultaine, Oleyl Betaine, Olivamidopropyl Betaine, Palmamidopropyl Betaine, Palmitamidopropyl Betaine, Palmitoyl Carnitine, Palm Kernelamidopropyl Betaine, Polytetrafluoroethylene Acetoxypropyl Betaine, Ricinoleamidopropyl Betaine, Sesamidopropyl Betaine, Soyamidopropyl Betaine, Stearamidopropyl Betaine, Stearyl Betaine, Tallowamidopropyl Betaine, Tallowamidopropyl Hydroxysultaine, Tallow Betaine, Tallow Dihydroxyethyl Betaine, Undecylenamidopropyl Betaine and Wheat Germamidopropyl Betaine. A preferred amphosurfactant is cocamidopropyl betaine (Cocoamidopropyl betaine). A particularly preferred amphoteric surfactant is capryl/capramidopropyl betaine (CAB) obtainable, for example, under the trade name Tegotens® B 810 from Th. Goldschmidt AG.

Alkylamido alkylamines (INCI Alkylamido Alkylamines) are amphoteric surfactants of the formula

R^VI—CO—NR^VII—(CH₂)_i—N(R^VIII)—(CH₂CH₂O)_j—(CH₂)_k-[CH(OH)]_l—CH₂—Z—OM

wherein R^VI is a saturated or unsaturated C_6-22 alkyl group, preferably C_8-18 alkyl group, more preferably a saturated C_10-16 alkyl group, for example; a saturated C_12-14 alkyl group; R^VII is hydrogen or a C_1-4 alkyl group, preferably H; i is a number from 1 to 10, preferably 2 to 5, particularly 2 or 3; R^VIII is hydrogen or CH₂COOM (for M see below); j is a number from 1 to 4, preferably 1 or 2, particularly 1; k is a number from 0 to 4, preferably 0 or 1; 1 is 0 or 1, wherein k is 1 if 1 is 1; Z is CO, SO₂, OPO(OR¹²) or P(O)(OR¹²), wherein R¹² is a C_1-4 alkyl group or M (see below); and M is hydrogen, an alkali metal, an alkaline earth metal or a protonated alkanolamine (e.g., protonated mono-, di- or triethanolamine).

Preferred representatives satisfy the formulas B1 to B4

R^VI—CO—NH—(CH₂)₂—N(R^VIII)—CH₂CH₂O—CH₂—COOM  (B1)

R^VI—CO—NH—(CH₂)₂—N(R^VIII)—CH₂CH₂O—CH₂CH₂—COOM  (B2)

R^VI—CO—NH—(CH₂)₂—N(R^VIII)—CH₂CH₂O—CH₂CH(OH)CH₂—SO₃M  (B3)

R^VI—CO—NH—(CH₂)₂—N(R^VIII)—CH₂CH₂O—CH₂CH(OH)CH₂—OPO₃HM  (B4)

wherein R^VI, R^VIII and M have the same meaning as in Formula B.

Exemplary alkylamido alkylamines include the following compounds named according to INCI: Cocoamphodipropionic Acid, Cocobetainamido Amphopropionate, DEA-Cocoamphodipropionate, Disodium Caproamphodiacetate, Disodium Caproamphodipropionate, Disodium Capryloamphodiacetate, Disodium Capryloamphodipropionate, Disodium Cocoamphocarboxyethylhydroxypropylsulfonate, Disodium Cocoamphodiacetate, Disodium Cocoamphodipropionate, Disodium Isostearoamphodiacetate, Disodium Isostearoamphodipropionate, Disodium Laureth-5-Carboxyamphodiacetate Carboxyamphodiacetate, Disodium Lauroamphodiacetate, Disodium Lauroamphodipropionate, Disodium Oleoamphodipropionate, Disodium PPG-2-Isodeceth-7-Carboxyamphodiacetate Carboxyamphodiacetate, Disodium Stearoamphodiacetate, Disodium Tallowamphodiacetate, Disodium Wheatgermamphodiacetate, Lauroamphodipropionic Acid, Quaternium-85, Sodium Caproamphoacetate, Sodium Caproamphohydroxypropylsulfonate, Sodium Caproamphopropionate, Sodium Capryloamphoacetate, Sodium Capryloamphohydroxypropylsulfonate, Sodium Capryloamphopropionate, Sodium Cocoamphoacetate, Sodium Cocoamphohydroxypropylsulfonate, Sodium Cocoamphopropionate, Sodium Cornamphopropionate, Sodium Isostearoamphoacetate, Sodium Isostearoamphopropionate, Sodium Lauroamphoacetate, Sodium Lauroamphohydroxypropylsulfonate, Sodium Lauroampho PG-Acetate Phosphate, Sodium Lauroamphopropionate, Sodium Myristoamphoacetate, Sodium Oleoamphoacetate, Sodium Oleoamphohydroxypropylsulfonate, Sodium Oleoamphopropionate, Sodium Ricinoleoamphoacetate, Sodium Stearoamphoacetate, Sodium Stearoamphohydroxypropylsulfonate, Sodium Stearoamphopropionate, Sodium Tallamphopropionate, Sodium Tallowamphoacetate, Sodium Undecylenoamphoacetate, Sodium Undecylenoamphopropionate, Sodium Wheat Germamphoacetate and Trisodium Lauroampho PG-Acetate Chloride Phosphate.

Soaps, oils, fats, paraffins or silicone oils, optionally deposited on carrier materials, are examples of foam inhibitors. Inorganic salts such as carbonates or sulfates, cellulose derivatives or silicates as well as their mixtures are examples of suitable carrier materials. In the context of the present application, preferred compositions comprise paraffins, preferably unbranched paraffins (n-paraffins) and/or silicones, preferably linear polymeric silicones having the structure (R₂SiO)_x and which are also called silicone oils.

Cleaning agents employed in the inventive process include anionic polymers as a second ingredient. All washing or cleaning active anionic polymers known to the person skilled in the art can be employed as the anionic polymers.

In preferred inventive processes the automatic dishwashing agent A comprises anionic polymer(s) in amounts of about 0.1 to about 40 wt. %, preferably about 0.2 to about 20 wt. %, particularly preferably about 0.5 to about 15 wt. % and especially from about 1 to about 10 wt. %, each based on total weight of the automatic dishwashing agent A. Corresponding agents have proved advantageous in the inventive processes, particularly with respect to optimal cleaning and rinsing results.

Accordingly, a particularly preferred subject matter of the present application is a process for cleaning tableware in an automatic dishwasher during which aqueous cleaning liquor present in the interior of the automatic dishwasher is at least partially removed from the interior of the automatic dishwasher at a time t. Further, an automatic dishwashing agent A comprising, based on total weight of the automatic dishwashing agent A—

a) 0.5 to 10 wt. % nonionic surfactant(s), and

b) 0.2 to 20 wt. % anionic polymer(s)

is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

Accordingly, a further preferred subject matter of the present application is a process for cleaning tableware in an automatic dishwasher, during which an aqueous wash liquor present in the interior of the automatic dishwasher is removed from the interior of the dishwasher in an amount of from about 5 to about 99 vol. %, preferably from about 10 to about 90 vol. %, particularly preferably from about 20 to about 80 vol. % and especially from about 40 to about 70 vol. % at a time t, wherein an automatic dishwashing agent A comprising, based on total weight of the automatic dishwashing agent A—

a) 0.5 to 10 wt. % nonionic surfactant(s), and

b) 0.2 to 20 wt. % anionic polymer(s)

is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

Suitable exemplary anionic polymers include polymeric polycarboxylates, particularly alkali metal salts of polyacrylic or polymethacrylic acid, for example, those with a relative molecular weight of 500 to 70,000 g/mol.

Particularly suitable polymers include polyacrylates, preferably having a molecular weight of 2,000 to 20,000 g/mol. Because of their superior solubility, preferred representatives of this group are again short-chain polyacrylates having molecular weights of 2,000 to 10,000 g/mol and, more particularly, 3,000 to 5,000 g/mol.

Further suitable copolymeric polycarboxylates include particularly those of acrylic acid with methacrylic acid and of acrylic acid or methacrylic acid with maleic acid. Copolymers of acrylic acid with maleic acid comprising about 50 to about 90 wt. % acrylic acid and about 50 to about 10 wt. % maleic acid have proven to be particularly suitable. Their relative molecular weight, based on free acids, generally ranges from about 2,000 to about 70,000 g/mol, preferably about 20,000 to about 50,000 g/mol and especially about 30,000 to about 40,000 g/mol.

Preferred inventive processes are those wherein the anionic polymer is a homopolymer and/or copolymer of acrylic acid or methacrylic acid.

Alternatively or in addition to the abovementioned polycarboxylates, anionic polymers employed in the inventive process can also comprise sulfonic acid groups.

Preferred inventive processes are those wherein the anionic polymer is a copolymer of—

i) unsaturated carboxylic acids,

ii) sulfonic acid groups containing monomers, or

iii) optional additional ionic or nonionogenic monomers.

Preferred monomers ii) containing sulfonic acid groups correspond to the formula —

R⁵(R⁶)C═C(R⁷)—X—SO₃H

wherein R⁵ to R⁷ independently are —H, —CH₃, a linear or branched, saturated alkyl group containing 2 to 12 carbon atoms, a linear or branched, mono- or polyunsaturated alkenyl group containing 2 to 12 carbon atoms, with —NH₂, —OH or —COOH substituted alkyl or alkenyl groups or —COOH or —COOR⁴, wherein R⁴ is a saturated or unsaturated, linear or branched hydrocarbon group containing 1 to 12 carbon atoms; and X is an optional spacer group chosen from —(CH₂)_n— with n=0 to 4, —COO—(CH₂)_k— with k=1 to 6, —C(O)—NH—C(CH₃)₂—, —C(O)—NH—C(CH₃)₂CH₂— and —C(O)—NH—CH(CH₂CH₃)—.

Among these monomers those are preferred of the formulas—

H₂C═CH—X—SO₃H

H₂C═C(CH₃)—X—SO₃H

HO₃S —X—(R⁶)C═C(R⁷)—X—SO₃H,

wherein R⁶ and R⁷ independently are —H, —CH₃, —CH₂CH₃, —CH₂CH₂CH₃, or —CH(CH₃)₂; and X is an optionally present spacer group chosen from —(CH₂)_n— with n=0 to 4, —COO—(CH₂)_k— with k=1 to 6, —C(O)—NH—C(CH₃)₂—, —C(O)—NH—C(CH₃)₂CH₂— and —C(O)—NH—CH(CH₂CH₃)—.

Accordingly, particularly preferred sulfonic acid-containing monomers include 1-acrylamido-1-propane sulfonic acid, 2-acrylamido-2-propane sulfonic acid, 2-acrylamido-2-methyl-1-propane sulfonic acid, 2-methacrylamido-2-methyl-1-propane sulfonic acid, 3-methacrylamido-2-hydroxypropane sulfonic acid, allyl sulfonic acid, methallyl sulfonic acid, allyloxybenzene sulfonic acid, methallyloxybenzene sulfonic acid, 2-hydroxy-3-(2-propenyloxy)propane sulfonic acid, 2-methyl-2-propene-1-sulfonic acid, styrene sulfonic acid, vinyl sulfonic acid, 3-sulfopropyl acrylate, 3-sulfopropyl methacrylate, sulfomethylacrylamide, sulfomethylmethacrylamide and mixtures of the cited acids or of their water-soluble salts.

Sulfonic acid groups can be present in the polymers in completely or partly neutralized form, meaning, the acidic hydrogen atom of the sulfonic acid groups can be replaced by metal ions, preferably alkali metal ions and more particularly sodium ions, in some or all of the sulfonic acid groups. The addition of copolymers containing partly or fully neutralized sulfonic acid groups is preferred according to the invention.

The molecular weight of the inventively preferred sulfo-copolymers used can be varied to adapt the properties of the polymer to the desired application requirement. Preferred automatic dishwashing agents include copolymers having molecular weights from about 2000 to about 200,000 gmol¹, preferably about 4000 to about 25,000 gmol¹ and especially about 5000 to about 15,000 gmol¹.

Further suitable anionic polymers include hydrophobically modified anionic polymers, for example, anionic polymers such as —

• • i) monomers from the group of the mono- or polyunsaturated carboxylic acids,
  • ii) monomers of the general formula R¹(R²)C═C(R³)—X—R⁴, wherein R¹ to R³ independently are —H, —CH₃ or —C₂H₅; X is an optional spacer group chosen from —CH₂—, —C(O)O— and —C(O)—NH—; and R⁴ is a straight chain or branched saturated alkyl group containing 2 to 22 carbon atoms or for an unsaturated, preferably aromatic group containing 6 to 22 carbon atoms, and
  • iii) optionally, further monomers.

Particularly preferred monomers i) from the group of the mono or polyunsaturated carboxylic acids are unsaturated carboxylic acids of the general formula R¹(R²)C═C(R³)COOH, in which R¹ to R³ independently of one another stand for —H, —CH₃, a linear or branched, saturated alkyl group containing 2 to 12 carbon atoms, a linear or branched, mono or polyunsaturated alkenyl group containing 2 to 12 carbon atoms, alkyl or alkenyl groups substituted by —NH₂, —OH or —COON as defined above or for —COOH or —COOR⁴, wherein R⁴ is a saturated or unsaturated, linear or branched hydrocarbon group containing 1 to 12 carbon atoms.

Accordingly, a particularly preferred subject matter of the present application is a process for cleaning tableware in an automatic dishwasher, during which aqueous cleaning liquor present in the interior of the automatic dishwasher is at least partially removed from the interior of the automatic dishwasher at a time t, wherein an automatic dishwashing agent A comprising, based on total weight of the automatic dishwashing agent A—

a) 0.5 to 10 wt. % nonionic surfactant(s), and

b) anionic polymer(s) containing

• • i. monomers from the group of mono- or polyunsaturated carboxylic acids
  • ii. monomers of the general formula R¹(R²)C═C(R³)—X—R⁴, wherein R¹ to R³ independently are —H, —CH₃ or —C₂H₅; X is an optional spacer group chosen from —CH₂—, —C(O)O— and —C(O)—NH—; and R⁴ is a straight chain or branched saturated alkyl group containing 2 to 22 carbon atoms or an unsaturated, preferably aromatic group containing 6 to 22 carbon atoms, and
  • iii. optional further monomers
    is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

Accordingly, a further preferred subject matter of the present application is a process for cleaning tableware in an automatic dishwasher, during which aqueous wash liquor present in the interior of the automatic dishwasher is removed from the interior of the dishwasher at a time t in an amount of from about 5 to about 99 vol. %, preferably from about 10 to about 90 vol. %, particularly preferably from about 20 to about 80 vol. % and especially from about 40 to about 70 vol. % of the wash liquor, wherein an automatic dishwashing agent A comprising, based on total weight of the automatic dishwashing agent A,—

a) 0.5 to 10 wt. % nonionic surfactant(s), and

b) anionic polymer(s) containing

• • i. monomers from the group of the mono- or polyunsaturated carboxylic acids
  • ii. monomers of the general formula R¹(R²)C═C(R³)—X—R⁴, wherein R¹ to R³ independently are —H, —CH₃ or —C₂H₅; X is an optional spacer group chosen from —CH₂—, —C(O)O— and —C(O)—NH—; and R⁴ is a straight chain or branched saturated alkyl group containing 2 to 22 carbon atoms, or an unsaturated, preferably aromatic group containing 6 to 22 carbon atoms, and
  • iii. optional further monomers
    is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

Particularly preferred carboxyl group-containing monomers i) of the above-mentioned hydrophobically modified anionic polymers include acrylic acid, methacrylic acid, ethacrylic acid, α-chloroacrylic acid, α-cyanoacrylic acid, crotonic acid, α-phenylacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid, methylenemalonic acid, sorbic acid, cinnamic acid or their mixtures.

Monomers of the general formula R¹ (R²)C═C(R³)—X—R⁴ can be added as the nonionic monomers ii). Particularly preferred monomers of this type include butene, isobutene, pentene, 3-methylbutene, 2-methylbutene, cyclopentene, hexene, 1-hexene, 2-methlypentene-1,3-methlypentene-1, cyclohexene, methylcyclopentene, cycloheptene, methylcyclohexene, 2,4,4-trimethylpentene-1,2,4,4-trimethylpentene-2,2,3-dimethylhexene-1,2,4-dimethylhexene-1,2,5-dimethlyhexene-1,3,5-dimethylhexene-1,4,4-dimethylhexene-1, ethylcyclohexyne, 1-octene, α-olefins containing 10 or more carbon atoms such as for example 1-decene, 1-dodecene, 1-hexadecene, 1-octadecene and C22-α-olefin, 2-styrene, α-methylstyrene, 3-methylstyrene, 4-propylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 1-vinylnaphthalene, 2-vinylnaphthalene, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate, hexyl acrylate, methyl methacrylate, N-(methyl)acrylamide, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, N-(2-ethylhexyl)acrylamide, octyl acrylate, octyl methacrylate, N-(octyl)acrylamide, lauryl acrylate, lauryl methacrylate, N-(lauryl)acrylamide, stearyl acrylate, stearyl methacrylate, N-(stearyl)acrylamide, behenyl acrylate, behenyl methacrylate and N-(behenyl)acrylamide or their mixtures.

In a particularly preferred embodiment, the copolymer d) contains, in addition to monomers i) and ii), a third monomer iii) from sulfonic acid group-containing monomers.

Preferred monomers containing sulfonic acid groups include those of the formula —

R⁵(R⁶)C═C(R⁷)—X—SO₃H

wherein R⁵ to R⁷ are independently —H, —CH₃, a linear or branched, saturated alkyl group containing 2 to 12 carbon atoms, a linear or branched, mono- or polyunsaturated alkenyl group containing 2 to 12 carbon atoms, alkyl or alkenyl groups substituted with —NH₂, —OH or —COOH or —COOH or —COOR⁴, wherein R⁴ is a saturated or unsaturated, linear or branched hydrocarbon group containing 1 to 12 carbon atoms; and X is an optional spacer group chosen from —(CH₂)_n— with n=0 to 4, —COO—(CH₂)_k— with k=1 to 6, —C(O)—NH—C(CH₃)₂— and —C(O)—NH—CH(CH₂CH₃)—.

Among these monomers, preferred are those of the formulas —

H₂C═CH—X—SO₃H

H₂C═C(CH₃)—X—SO₃H

HO₃S—X—(R⁶)C═C(R⁷)—X—SO₃H

wherein R⁶ and R⁷ are independently —H, —CH₃, —CH₂CH₃, —CH₂CH₂CH₃ or —CH(CH₃)₂; and X is an optional spacer group chosen from —(CH₂)_n— with n=0 to 4, —COO—(CH₂)_k— with k=1 to 6, —C(O)—NH—C(CH₃)₂— and —C(O)—NH—CH(CH₂CH₃)—.

Accordingly, particularly preferred sulfonic acid-containing monomers include 1-acrylamido-1-propane sulfonic acid, 2-acrylamido-2-propane sulfonic acid, 2-acrylamido-2-methyl-1-propane sulfonic acid, 2-methacrylamido-2-methyl-1-propane sulfonic acid, 3-methacrylamido-2-hydroxypropane sulfonic acid, allyl sulfonic acid, methallyl sulfonic acid, allyloxybenzene sulfonic acid, methallyloxybenzene sulfonic acid, 2-hydroxy-3-(2-propenyloxy)propane sulfonic acid, 2-methyl-2-propene-1-sulfonic acid, styrene sulfonic acid, vinyl sulfonic acid, 3-sulfopropyl acrylate, 3-sulfopropyl methacrylate, sulfomethylacrylamide, sulfomethylmethacrylamide and mixtures of the cited acids or of their water-soluble salts.

The sulfonic acid groups may be present in the polymers completely or partly in neutralized form, meaning, the acidic hydrogen atom of the sulfonic acid groups can be replaced by metal ions, preferably alkali metal ions and more particularly sodium ions, in some or all of the sulfonic acid groups. The addition of copolymers containing partly or fully neutralized sulfonic acid groups is preferred according to the invention.

The molecular weight of the inventively preferred sulfo-copolymers used can be varied to adapt the properties of the polymer to the desired application requirement. Preferred automatic dishwashing agents are characterized in that the copolymers have molecular weights from about 2000 to about 200,000 gmol⁻¹, preferably about 4000 to about 25,000 gmol⁻¹ and especially about 5000 to about 15,000 gmol⁻¹.

Accordingly, a further particularly preferred subject matter of the present application is a process for cleaning tableware in an automatic dishwasher during which aqueous cleaning liquor present in the interior of the automatic dishwasher is at least partially removed from the interior of the automatic dishwasher at a time t, wherein an automatic dishwashing agent A, comprising, based on the total weight of the automatic dishwashing agent A—

a) 0.5 to 10 wt. % nonionic surfactant(s), and

b) anionic polymer(s), containing

• • i. monomers from the group of the mono- or polyunsaturated carboxylic acids,
  • ii. monomers of the general formula R¹(R²)C═C(R³)—X—R⁴, wherein R¹ to R³ independently are —H, —CH₃ or —C₂H₅; X is an optional spacer group chosen from —CH₂—, —C(O)O— and —C(O)—NH—, and R⁴ is a straight chain or branched saturated alkyl group containing 2 to 22 carbon atoms or an unsaturated, preferably aromatic group containing 6 to 22 carbon atoms, and/or
  • iii. sulfonic acid groups containing monomers
    is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

Accordingly, a further preferred subject matter of the present application is a process for cleaning tableware in an automatic dishwasher during which aqueous wash liquor present in the interior of the automatic dishwasher is removed from the interior of the dishwasher at a time t in an amount of from about 5 to about 99 vol. %, preferably from about 10 to about 90 vol. %, particularly preferably from about 20 to about 80 vol. % and especially from about 40 to about 70 vol. % of the wash liquor, wherein an automatic dishwashing agent A comprising, based on total weight of the automatic dishwashing agent A—

a) 0.5 to 10 wt. % nonionic surfactant(s), and

b) anionic polymer(s), containing

• • i. monomers from the group of the mono- or polyunsaturated carboxylic acids
  • ii. monomers of the general formula R¹(R²)C═C(R³)—X—R⁴, wherein R¹ to R³ independently are —H, —CH₃ or —C₂H₅; X is an optional spacer group chosen from —CH₂—, —C(O)O— and —C(O)—NH—; and R⁴ is a straight chain or branched saturated alkyl group containing 2 to 22 carbon atoms, or an unsaturated, preferably aromatic group containing 6 to 22 carbon atoms, and/or
  • iii. sulfonic acid groups containing monomers
    is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

The automatic dishwashing agent employed in the inventive process can have one or more builders as additional ingredients. These builders include silicates, carbonates and organic co-builders, as well as phosphates.

Organic co-builders include polycarboxylates/polycarboxylic acids, polymeric polycarboxylates, aspartic acid, polyacetals, dextrins, and other organic co-builders. These classes of substances are described below.

Useful organic builders are, for example, polycarboxylic acids that can be used in the form of the free acid and/or their sodium salts, polycarboxylic acids in this context being understood to be carboxylic acids that carry more than one acid function. These include citric acid, adipic acid, succinic acid, glutaric acid, malic acid, tartaric acid, maleic acid, fumaric acid, sugar acids, amino carboxylic acids, nitrilotriacetic acid (NTA), providing such use is not ecologically unsafe, and mixtures thereof. Besides their building effect, the free acids also typically have the property of an acidifying component and hence also serve to establish a relatively low and mild pH of laundry detergents and cleaning compositions. Citric acid, succinic acid, glutaric acid, adipic acid, gluconic acid and any mixtures thereof are particularly mentioned in this regard.

Particularly preferred inventive automatic dishwashing agents comprise citrate as one of their essential builders. According to the invention, preferred processes include those in which the dishwashing agent A comprises, based on total weight of the automatic dishwashing agent A, about 5 to about 60 wt. %, preferably about 10 to about 50 wt. % and particularly about 15 to about 40 wt. % citrate.

Accordingly, a preferred subject matter of the present application is a process for cleaning tableware in an automatic dishwasher during which aqueous cleaning liquor present in the interior of the automatic dishwasher is at least partially removed from the interior of the automatic dishwasher at a time t, wherein an automatic dishwashing agent A, comprising, based on the total weight of the automatic dishwashing agent A—

a) 0.5 to 10 wt. % nonionic surfactant(s),

b) 0.2 to 20 wt. % anionic polymer(s), and

c) 10 to 50 wt. % citrate

is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

Further preferred is a process for cleaning tableware in an automatic dishwasher during which aqueous wash liquor present in the interior of the automatic dishwasher is removed from the interior of the dishwasher at a time t in an amount of from about 5 to about 99 vol. %, preferably from about 10 to about 90 vol. %, particularly preferably from about 20 to about 80 vol. % and especially from about 40 to about 70 vol. % of the wash liquor, wherein an automatic dishwashing agent A comprising, based on total weight of the automatic dishwashing agent A—

a) 0.5 to 10 wt. % nonionic surfactant(s),

b) 0.2 to 20 wt. % anionic polymer(s), and

c) 10 to 50 wt. % citrate

is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

In the washing and cleaning agent industry, among the many commercially available phosphates, alkali metal phosphates are important, with pentasodium or pentapotassium triphosphates (sodium or potassium tripolyphosphate) particularly preferred.

“Alkali metal phosphates” collectively refers to alkali metal (more particularly sodium and potassium) salts of the various phosphoric acids in which metaphosphoric acids (HPO₃)_n and orthophosphoric acid (H₃PO₄) and representatives of higher molecular weight can be differentiated. The phosphates combine several inherent advantages: They act as alkalinity sources, prevent lime deposits on machine parts and lime incrustations in fabrics and, in addition, contribute towards the cleansing power.

Industrially important phosphates include pentasodium triphosphate, Na₅P₃O₁₀ (sodium tripolyphosphate) as well as the corresponding potassium salt pentapotassium triphosphate K₅P₃O₁₀ (potassium tripolyphosphate). According to the invention, sodium potassium tripolyphosphates are again preferably employed.

In the context of the present invention, if phosphates are incorporated as the active washing or cleaning substances in the automatic dishwashing agent, then preferred compositions comprise this/these phosphate(s), preferably alkali metal phosphate(s), particularly preferably pentasodium or pentapotassium triphosphate (sodium or potassium tripolyphosphate) in amounts of about 5 to about 60 wt. %, preferably about 10 to about 50 wt. % and especially about 15 to about 40 wt. %, each based on the weight of the automatic dishwashing agent.

In a preferred process variant, complexants (preferably phosphonates) are added to complement the combination of active substances of nonionic surfactant and anionic polymer. Particularly preferred automatic dishwashing processes are those wherein the dishwashing agent A comprises a complexant, preferably 1-hydroxyethane-1,1-diphosphonic acid and/or methylglycine diacetic acid.

In addition to 1-hydroxyethane-1,1-diphosphonic acid, phosphonate complexants include a series of different compounds such as diethylenetriamine penta(methylene phosphonic acid) (DTPMP). Hydroxyalkane phosphonates or aminoalkane phosphonates are particularly preferred in this application. Among the hydroxyalkane phosphonates, 1-hydroxyethane-1,1-diphosphonate (HEDP) is of particular importance as the cobuilder. It is normally added as the sodium salt, the disodium salt reacting neutral and the tetrasodium salt reacting alkaline (pH 9). Ethylenediamine tetramethylene phosphonate (EDTMP), diethylenetriamine pentamethylene phosphonate (DTPMP) and their higher homologs are preferably chosen as the aminoalkane phosphonates. They are preferably added in the form of the neutral-reacting sodium salts (e.g., as the hexasodium salt of EDTMP or as the hepta and octasodium salt of DTPMP). Of the class of phosphonates, HEDP is preferably used as the builder. The aminoalkane phosphonates additionally possess a pronounced ability to complex heavy metals. Accordingly, it can be preferred, particularly where the agents also contain bleach, to use aminoalkane phosphonates, particularly DTPMP, or mixtures of the mentioned phosphonates.

In the context of this application, a preferred automatic dishwashing agent A comprises one or more phosphonates from the group—

• • a) aminotrimethylene phosphonic acid (ATMP) and/or its salts;
  • b) ethylenediamine tetra(methylene phosphonic acid) (EDTMP) and/or its salts;
  • c) diethylenetriamine penta(methylene phosphonic acid) (DTMP) and/or its salts;
  • d) 1-hydroxyethane-1,1-diphosphonic acid (HEDP) and/or its salts;
  • e) 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC) and/or its salts;
  • f) hexamethylenediamine tetra(methylene phosphonic acid) (HDTMP) and/or its salts; and/or
  • g) nitrilo tri(methylene phosphonic acid) (NTMP) and/or its salts.

Particularly preferred automatic dishwashing agents comprise 1-hydroxyethane-1,1-diphosphonic acid (HEDP) or diethylenetriamine penta(methylene phosphonic acid) (DTMP) as the phosphonates.

Of course the inventive automatic dishwashing agents can have two or more different phosphonates. Particularly preferred automatic dishwashing agents A include both 1-hydroxyethane-1,1-diphosphonic acid (HEDP) and diethylenetriamine penta(methylene phosphonic acid) (DTMP) as the phosphonates, wherein the weight ratio of HEDP to DTPMP is from 20:1 to 1:20, preferably from 15:1 to 1:15 and especially from 10:1 to 1:10.

In a preferred embodiment of the present invention, the weight fraction of phosphonate(s) to total weight of the automatic dishwashing agent is less than the weight fraction of the polymer(s) b). In other words, those agents are particularly preferred in which the ratio of the weight fraction of polymer b) to the weight fraction of the phosphonate is 200:1 to 2:1, preferably 150:1 to 2:1, particularly preferably 100:1 to 2:1, quite particularly preferably 80:1 to 3:1 and especially 50:1 to 5:1.

The weight fraction of these complexants, in particular, the sum of the weight fractions of 1-hydroxyethane-1,1-diphosphonic acid (HEDP) and methyl glycine diacetic acid (MGDA), is preferably about 0.5 to about 14 wt. %, preferably about 1 to about 12 wt. % and especially about 2 to about 8 wt. %.

A further preferred subject matter of the present application is a process for cleaning tableware in an automatic dishwasher during which aqueous cleaning liquor present in the interior of the automatic dishwasher is at least partially removed from the interior of the automatic dishwasher at a time t, wherein an automatic dishwashing agent A comprising, based on total weight of the automatic dishwashing agent A—

a) 0.5 to 10 wt. % nonionic surfactant(s),

b) 0.2 to 20 wt. % anionic polymer(s),

c) 15 to 40 wt. % phosphate or 15 to 40 wt. % citrate, and

d) 0.5 to 8 wt. % phosphonate(s),

is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

Further preferred is a process for cleaning tableware in an automatic dishwasher during which aqueous wash liquor present in the interior of the automatic dishwasher is removed from the interior of the dishwasher at a time t in an amount of from about 5 to about 99 vol. %, preferably from about 10 to about 90 vol. %, particularly preferably from about 20 to about 80 vol. % and especially from about 40 to about 70 vol. % of the wash liquor, wherein an automatic dishwashing agent A comprising, based on total weight of the automatic dishwashing agent A—

a) 0.5 to 10 wt. % nonionic surfactant(s),

b) 0.2 to 20 wt. % anionic polymer(s),

c) 15 to 40 wt. % phosphate or 15 to 40 wt. % citrate,

d) 0.5 to 8 wt. % phosphonate(s),

is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

Enzymes can also be incorporated in the inventive process in order to boost cleaning power. These particularly include proteases, amylases, lipases, hemicellulases, cellulases or oxidoreductases, as well as preferably their mixtures. In principle, these enzymes are of natural origin; improved variants based on the natural molecules are available for use in laundry detergents or cleaning compositions and accordingly are preferred. The detergents or cleaning compositions preferably comprise enzymes in total quantities of about 1×10⁻⁶ to about 5 weight percent based on active protein. Protein concentration can be determined using known methods (e.g., the BCA Process or the biuret process).

Preferred proteases are those of the subtilisin type. Examples include the subtilisins BPN′ and Carlsberg as well as their further developed forms, the protease PB92, the subtilisins 147 and 309, the alkaline protease from Bacillus lentus, subtilisin DY and those enzymes of the subtilases no longer classified in the stricter sense as subtilisins: thermitase, proteinase K and the proteases TW3 und TW7.

Examples of further useable amylases according to the invention include α-amylases from Bacillus licheniformis, from B. amyloliquefaciens, from B. stearothermophilus, from Aspergillus niger and A. oryzae, as well as their improved further developments for use in washing and cleaning agents. Moreover, for these purposes, attention should be drawn to the α-amylase from Bacillus sp. A 7-7 (DSM 12368) and the cyclodextrin-glucanotransferase (CGTase) from B. agaradherens (DSM 9948).

According to the invention, lipases or cutinases can also be incorporated, particularly due to their triglyceride cleaving activities, but also in order to produce in situ peracids from suitable preliminary steps. These include the available or further developed lipases originating from Humicola lanuginosa (Thermomyces lanuginosus), particularly those with the amino acid substitution D96L. Moreover, suitable cutinases include those originally isolated from Fusarium solani pisi and Humicola insolens. Further suitable are lipases or cutinases whose starting enzymes were originally isolated from Pseudomonas mendocina and Fusarium solanii.

In addition, enzymes summarized under the term hemicellulases can be added. These include mannanases, xanthanlyases, pectinlyases (=pectinases), pectinesterases, pectatlyases, xyloglucanases (=xylanases), pullulanases und β-glucanases.

To increase the bleaching action, oxidoreductases, for example, oxidases, oxygenases, katalases, peroxidases like halo-, chloro-, bromo-, lignin-, glucose- or manganese-peroxidases, dioxygenases or laccases (phenoloxidases, polyphenoloxidases) can be incorporated according to the invention. Advantageously, additional, preferably organic, particularly preferably aromatic compounds are added that interact with the enzymes to enhance the activity of the relative oxidoreductases or to facilitate the electron flow (mediators) between the oxidizing enzymes and the stains over strongly different redox potentials.

Enzymes can be added in forms established according to the prior art. Included here, for example, are solid preparations obtained by granulation, extrusion or lyophilization, or particularly liquid compositions or compositions in the form of gels, enzyme solutions, advantageously highly concentrated, of low moisture content and/or mixed with stabilizers.

As an alternative application form, the enzymes can also be encapsulated, for example, by spray drying or extrusion of the enzyme solution together with a preferably natural polymer or in the form of capsules, for example those in which the enzyme is embedded in a solidified gel, or in those of the core-shell type, in which an enzyme-containing core is covered with a water-, air- and/or chemical-impervious protective layer. Further active principles, for example stabilizers, emulsifiers, pigments, bleaches or colorants can be applied in additional layers. Such capsules are made using known methods, for example by vibratory granulation or roll compaction or by fluidized bed processes. Advantageously, these types of granulates, for example with an applied polymeric film former are dust-free and as a result of the coating are storage stable.

In addition, it is possible to formulate two or more enzymes together so that a single granulate exhibits a plurality of enzymatic activities.

A protein and/or enzyme can be protected, particularly in storage, against deterioration such as inactivation, denaturation or decomposition, for example, through physical influences, oxidation or proteolytic cleavage. Inhibition of the proteolysis is particularly preferred during microbial preparation of proteins and/or enzymes, particularly when the compositions also contain proteases. For this use, washing or cleaning agents can comprise stabilizers. The provision of these types of agents represents a preferred embodiment of the present invention.

Preferred automatic dishwashing processes are those in which the dishwashing agent A comprises, based on total weight of the automatic dishwashing agent A, about 0.2 to about 5 wt. %, preferably about 0.5 to about 5 wt. % and particularly about 1 to about 4 wt. % enzyme(s).

A further preferred subject matter of the present application is a process for cleaning tableware in an automatic dishwasher during which aqueous cleaning liquor present in the interior of the automatic dishwasher is at least partially removed from the interior of the automatic dishwasher at a time t, wherein an automatic dishwashing agent A comprising, based on total weight of the automatic dishwashing agent A—

a) 0.5 to 10 wt. % nonionic surfactant(s),

b) 0.2 to 20 wt. % anionic polymer(s), preferably sulfonic acid group-containing polymer(s),

c) 15 to 40 wt. % phosphate or 15 to 40 wt. % citrate, and

d) 0.5 to 5 wt. % enzyme(s),

is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

Further preferred is a process for cleaning tableware in an automatic dishwasher during which aqueous wash liquor present in the interior of the automatic dishwasher is removed from the interior of the dishwasher at a time t in an amount of from about 5 to about 99 vol. %, preferably from about 10 to about 90 vol. %, particularly preferably from about 20 to about 80 vol. % and especially from about 40 to about 70 vol. % of the wash liquor, wherein an automatic dishwashing agent A comprising, based on total weight of the automatic dishwashing agent A—

a) 0.5 to 10 wt. % nonionic surfactant(s),

b) 0.2 to 20 wt. % anionic polymer(s), preferably sulfonic acid group-containing polymer(s),

c) 15 to 40 wt. % phosphate or 15 to 40 wt. % citrate, and

d) 0.5 to 5 wt. % enzyme(s),

is metered into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t.

Preferred automatic dishwashing agents A additionally comprise one or more bleaching agents. Among the compounds which serve as bleaching agents and liberate H₂O₂ in water, sodium percarbonate, sodium perborate tetrahydrate and sodium perborate monohydrate are of particular use. Examples of further bleaching agents that may be used are peroxypyrophosphates, citrate perhydrates and H₂O₂-liberating peracidic salts or peracids, such as perbenzoates, peroxyphthalates, diperoxyazelaic acids, phthaloimino peracids or diperoxydodecanedioic acids. Moreover, bleaching agents from the group of the organic bleaching agents can also be used. Typical organic bleaching agents include diacyl peroxides such as dibenzoyl peroxide. Further typical organic bleaching agents include peroxy acids, wherein the alkylperoxy acids and the arylperoxy acids may be named as examples.

According to the invention, preferred processes include those wherein the dishwashing agent A comprises, based on total weight of the automatic dishwashing agent A, about 1 to about 20 wt. %, preferably about 2 to about 15 wt. % and particularly about 4 to about 12 wt. % sodium percarbonate.

Chlorine- or bromine-releasing substances can also be incorporated as bleaching agents. Suitable chlorine- or bromine-releasing materials include, for example, heterocyclic N-bromamides and N-chloramides, for example trichloroisocyanuric acid, tribromoisocyanuric acid, dibromoisocyanuric acid and/or dichloroisocyanuric acid (DICA) and/or salts thereof with cations such as potassium and sodium. Hydantoin compounds, such as 1,3-dichloro-5,5-dimethyl hydantoin, are also suitable.

In order to achieve an improved bleaching action for cleaning at temperatures of about 60° C. and below, the inventively employed automatic dishwashing agents can additionally comprise bleach activators. Bleach activators which can be used are compounds which, under perhydrolysis conditions, yield aliphatic peroxycarboxylic acids having preferably 1 to 10 carbon atoms, in particular 2 to 4 carbon atoms, and/or optionally substituted perbenzoic acid. Substances, which carry O-acyl and/or N-acyl groups of said number of carbon atoms and/or optionally substituted benzoyl groups, are suitable. Polyacylated alkylenediamines are preferred, tetraacetyl ethylenediamine (TAED) having proven to be particularly suitable.

These bleach activators, especially TAED, are preferably employed in amounts of up to about 10 wt. %, particularly about 0.1 to about 8 wt. %, especially about 2 to about 8 wt. % and particularly preferably about 2 to about 6 wt. %, each based on the total weight of the bleach activator-containing composition.

In addition to, or instead of conventional bleach activators, so-called bleach catalysts may also be incorporated. These substances include bleach-boosting transition metal salts or transition metal complexes such as manganese-, iron-, cobalt-, ruthenium- or molybdenum-salen or -carbonyl complexes. Manganese, iron, cobalt, ruthenium, molybdenum, titanium, vanadium and copper complexes with nitrogen-containing tripod ligands, as well as cobalt-, iron-, copper- and ruthenium-amine complexes may also be employed as the bleach catalysts.

Complexes of manganese in the valence state II, III, IV or V which preferably comprise one or a plurality of macrocyclic ligands with the donor functions N, NR, PR, O and/or S are particularly preferably included. Ligands having nitrogen donor functions are preferably employed. In this regard, it is particularly preferred to incorporate bleach catalyst(s) into compositions according to the invention which comprise 1,4,7-trimethyl-1,4,7-triazacyclononane (Me-TACN), 1,4,7-triazacyclononane (TACN), 1,5,9-trimethyl-1,5,9-triazacyclododecane (Me-TACD), 2-methyl-1,4,7-trimethyl-1,4,7-triazacyclononane (Me/Me-TACN) and/or 2-methyl-1,4,7-triazacyclononane (Me/TACN) as the macromolecular ligands. Suitable manganese complexes are for example [Mn^III₂(μ-O)₁(μ-OAc)₂(TACN)₂](CIO₄)₂, [Mn^IIIMn^IV(μ-O)₂(μ-OAc)₁(TACN)₂](BPh₄)₂, [Mn^IV₄(μ-O)₆(TACN)₄](CIO₄)₄, [Mn^III₂(μ-O)₁(μ-OAc)₂(Me-TACN)₂](CIO₄)₂, [Mn^IIIMn^IV(μ-O)₁(μ-OAc)₂(Me-TACN)₂](CIO₄)S, [Mn^IV₂(μ-O)₃(Me-TACN)₂](PF₆)₂ and [Mn^IV₂(μ-O)₃(Me/Me-TACN)₂](PF₆)₂(OAc═OC(O)CH₃).

Inventively preferred automatic dishwashing agents additionally comprise a bleach catalyst chosen from bleach boosting transition metal salts and transition metal complexes, preferably from complexes of manganese with 1,4,7-trimethyl-1,4,7-triazacyclononane (Me₃-TACN) or 1,2,4,7-tetramethyl-1,4,7-triazacyclononane (Me₄-TACN), as these bleach catalysts particularly contribute to an significantly improved cleaning result.

The abovementioned bleach boosting transition metal complexes, especially those with the central atoms Mn and Co, are added in usual amounts, preferably in an amount of up to about 5 wt. %, particularly from about 0.01 wt. % to about 2 wt. % and particularly preferably about 0.05 to about 0.8 wt. %, each based on the total weight of the automatic dishwashing agent A.

In addition to active substances present in the automatic dishwashing agent, pH of the added automatic dishwashing agent has proven relevant for cleaning, rinsing and drying results of the inventive process. Therefore, particularly good results are attained with automatic dishwashing agents, whose 1% conc. aqueous solution (20° C.) exhibits a pH above about 7, preferably from about 7 to about 12 and particularly preferably from about 9 to about 11. Accordingly, corresponding processes wherein the automatic dishwashing agent A exhibits a pH (1% conc. aqueous solution at 20° C.) above about 7, preferably from about 7 to about 12 and particularly preferably from about 9 to about 11, are likewise inventively preferred.

The surprising advantages of the inventive process become evident particularly in those automatic dishwashing processes in which the wash water has not been softened. (“Wash water” is the water used for washing). Accordingly, the wash water used for carrying out the inventive process preferably exhibits a hardness above about 5° dH, preferably above about 10° dH, particularly preferably above about 15° dH and in particular above about 20° dH.

The inventively employed automatic dishwashing agent A can be manufactured in solid or liquid form, but can also exist as a combination of solid and liquid product formats.

Powders, granulates, extrudates or compactates, especially tablets, are suitable solid product formats. Liquid product formats, preferably based on water and/or organic solvents, can be thickened, for example, in the form of gels.

The inventively employed automatic dishwashing agents A can be manufactured as a single phase or multi phase product. Automatic dishwashing agents with one, two, three or four phases are especially preferred. Automatic dishwashing agents in the form of a prefabricated unit dose with two or more phases are particularly preferred.

Individual phases of a multi-phase agent can have the same or different aggregation states. Automatic dishwashing agents having at least two different solid phases and/or at least two liquid phases and/or at least one solid and at least one liquid phase are particularly preferred. Inventive processes wherein the automatic dishwashing agent A is in solid form are preferred, however, due to improved cleaning, rinsing and drying results.

The automatic dishwashing agents A are preferably prefabricated as unit doses. These unit doses preferably contain the necessary quantity of washing or cleaning active substances for one cleaning cycle. Preferred unit doses weigh from about 12 to about 30 g, preferably from about 14 to about 26 g and especially from about 15 to about 22 g.

Volumes of the abovementioned unit doses and their three-dimensional shape are particularly preferably chosen such that the prefabricated units can be dosed by being placed in the dosing chamber of a dishwasher. Consequently, the volume of the unit dose is preferably from about 10 to about 35 ml, preferably from about 12 to about 30 ml and especially from about 15 to about 25 ml.

Automatic dishwashing agents according to the invention, in particular, prefabricated unit doses, preferably have a water-soluble coating.

In an alternative product format the automatic dishwashing agent A used in the inventive process is metered into the interior of the dishwasher by a water-insoluble storage reservoir. This storage reservoir preferably has two or more chambers in which the automatic dishwashing agent A is present, for example, in the form of partial formulations that are separated from each other. The water-insoluble storage reservoir can be integrated into the dishwasher, but can also be in the form of a two or multi-chamber bottle.

As described in the introduction, the inventive cleaning processes compared to conventional processes exhibit an improved cleaning and rinsing action, as well as an improved drying of the cleaned tableware. Use of an inventive automatic dishwashing process for reducing the formation of deposits in automatic dishwashing or for improving the drying in automatic dishwashing are further subject matters of this application.

EXAMPLES

Drying, deposition and cleaning performance of an automatic dishwashing process was determined as a function of the type of metering of the added automatic dishwashing agent.

For this, tableware was cleaned with 33 ml (16.5 ml F1 and 16.5 ml F2) of an automatic dishwashing agent at a water hardness of 21° dH in an automatic dishwasher (Miele 1730; Program 55° Normal 3 in 1 Extra Drying).

The composition of the added dishwashing agents F1 and F2 can be seen in the following Table:

	Raw material	F1 [wt. %]	F2 [wt. %]
	KTTP	17.5	10.0
	nonionic surfactant	4.0	—
	protease	2.0	—
	amylase	1.0	—
	phosphonate	3.0	5.0
	thickener	4.0	—
	organic solvent	3.0	3.0
	anionic polymer	—	8.6
	soda	—	7.0
	water, misc.	add 100	add 100

The following three experiments were carried out:

Experiment V1—16.5 ml of each of the compositions F1 and F2 were simultaneously metered into the interior of the machine in the main wash cycle of the dishwashing process.
Experiment V2—12.5 ml of composition F1 and 16.5 ml of composition F2 were metered into the interior of the machine in the main wash cycle of the dishwashing process; in addition in the following rinse cycle (after a partial exchange of wash water) 4 ml of composition F1 were metered into the interior of the machine.
Experiment E1—14.5 ml of composition F1 and F2 ml of composition F2 were simultaneously metered into the interior of the machine in the main wash cycle of the dishwashing process; in addition in the following rinse cycle (after a partial exchange of wash water) 2 ml of each of the compositions F1 and F2 were metered into the interior of the machine.

In regard to the cleaning performance (determined according to IKW), no significant differences were observed between both process variants.

Drying index was determined according to the EN specification. The results are presented in the following Table (the reported values are the mean of 3 experiments):

	V1	V2	E1
Drying index	0.60	0.85	0.80
Deposit formation	No deposits	Deposit formation	No deposits

Based on results in experiment V1, the drying index could consequently be improved in experiment V2 due to the subsequent metering of a surfactant-containing cleaning agent; however, the formation of deposits on the surface of the dishes was observed in both cases. Only by subsequent metering of surfactant and anionic polymer in experiment E1 could both good drying and deposition results be obtained.

Claims

1. Process for cleaning tableware in an automatic dishwasher comprising:

at least partially removing aqueous cleaning liquor present in an interior of the automatic dishwasher from the interior of the automatic dishwasher at a time t, and

metering an automatic dishwashing agent A into the interior of the automatic dishwasher in a quantity m1 at a time t1<t and in a quantity m2 at a time t2>t,

wherein the dishwashing agent A comprises a) surfactant(s), and b) anionic polymer(s).

2. Process according to claim 1 wherein the surfactant(s) in the automatic dishwashing agent A is at least a non-ionic surfactant present in an amount of 0.1 to 30 wt. %, based on total weight of the automatic dishwashing agent A.

3. Process according to claim 1 wherein the anionic polymer(s) in the automatic dishwashing agent A is present in an amount of 0.1 to 40 wt. %, based on total weight of the automatic dishwashing agent A.

4. Process according to claim 1 wherein the anionic polymer(s) is at least a homopolymer and/or copolymer of acrylic acid or methacrylic acid.

5. Process according to claim 1 wherein the anionic polymer(s) is at least a copolymer of

i) unsaturated carboxylic acids,

ii) sulfonic acid groups containing monomers, and

iii) optionally, ionic or nonionogenic monomers.

6. Process according to claim 1 wherein the automatic dishwashing agent A comprises

a) 0.5 to 10 wt. % nonionic surfactant(s),

b) 0.2 to 20 wt. % sulfonic acid group-containing polymer(s),

c) 10 to 40 wt. % phosphate or 10 to 40 wt. % citrate, and

d) 0.5 to 5 wt. % enzyme(s).

7. Process according to claim 1 wherein the dishwashing agent A further comprises 1 to 20 wt. % sodium percarbonate, based on total weight of the automatic dishwashing agent A.

8. Process according to claim 1 wherein the dishwashing agent A further comprises 0.01 to 2 wt. % bleach catalyst, based on total weight of the automatic dishwashing agent A.

9. Process according to claim 1 wherein the dishwashing agent A is in liquid form.

10. Process according to claim 1 wherein the weight ratio of the metered amounts m1 and m2 is from 20:1 to 2:1.

11. Process according to claim 1 wherein the time between times t1 and t2 is from 5 to 50 minutes.

12. Process according to claim 1 wherein the temperature of the wash liquor at time t1 is from 12 to 45° C.

13. Process according to claim 1 wherein the temperature of the wash liquor at time t2 is from 30 to 65° C.

14. Process according to claim 1 wherein the process improves drying in automatic dishwashing.

15. Process according to claim 1 wherein the process reduces formation of deposits in automatic dishwashing.